초록 ▼

An implantable valve for allowing the passage of cerebrospinal fluid (CSF) from a ventricle of the brain to a suitable drainage location in the body includes a housing having an inlet and outlet with valving means in the housing to control fluid flow from the inlet to the outlet. The valving means i

An implantable valve for allowing the passage of cerebrospinal fluid (CSF) from a ventricle of the brain to a suitable drainage location in the body includes a housing having an inlet and outlet with valving means in the housing to control fluid flow from the inlet to the outlet. The valving means includes various parts which are coaxially aligned between the inlet and outlet, the valving means having a valve seat, a valve closure means, a fluid flow restrictor means and a positioning means to control variable positioning of the valve closure means relative to the parts of the valving means. The valving means is actuable in response to applied pressure differentials, and regulates passage of CSF from the ventricular spaces to the drainage location. When the pressure differential is relatively small, the valve operates in a constant pressure mode to maintain a predetermined pressure differential across the valve. In response to a sudden increase in differential pressure, the valve operates in a constant flow mode to maintain a desired relatively constant CSF flow rate through the valve. Above a predetermined pressure differential, the valve operates in a constant pressure mode to maintain a predetermined maximum pressure differential across the valve.

대표청구항 ▼

A valve for controlling the passage of body fluids from a first location in the body to a second location, comprising: a bio-compatible housing having an interior passageway; inlet port means for establishing fluid communication between said interior passageway and the first location; outlet port me

A valve for controlling the passage of body fluids from a first location in the body to a second location, comprising: a bio-compatible housing having an interior passageway; inlet port means for establishing fluid communication between said interior passageway and the first location; outlet port means for establishing fluid communication between said interior passageway and the second location; valve closure means for providing a first valving mode in which fluid flow through said passageway is prevented in the absence of a first predetermined pressure differential between said inlet port means and said outlet port means; a first valving surface located along said interior passageway including, progressing from said inlet port means to said outlet port means, a first portion having a generally constant first diameter, a second portion having a generally constant second diameter less than said first diameter, and a third portion having a generally constant third diameter greater than said second diameter; a second valving surface being displaceable along the axis of said passageway in a direction away from said inlet port means in response to an increase in pressure differential between said inlet port means and said outlet port means thereby causing said second valving surface to successively coact with said first, second and third portions of said first valving surface to provide second, third and fourth valving modes, thereby in said second valving mode fluid flow occurs between said inlet port means and said outlet port means so as to maintain a first substantially constant predetermined pressure differential between said inlet port means and said outlet port means, in said third valving mode fluid flow remains substantially constant through said passageway notwithstanding changes in differential pressure between said inlet port means and said outlet port means, and in said fourth valving mode fluid flow occurs between said inlet port means and said outlet port means to maintain a second substantially constant predetermined pressure differential between said inlet port means and said outlet port means, said second pressure differential being greater than said first pressure differential.